Upon cutting a workpiece part free from a workpiece during processing of the workpiece (e.g., punching the workpiece), the workpiece part often times needs to be removed from the processing region of a machine tool used to process the workpiece or from a support plane that supports the workpiece. Accordingly, the workpiece part may be moved along the support plane on a workpiece table, for example, so that the workpiece part can be tipped over the edge of the workpiece table. In some examples, the workpiece part may be positioned over a parts chute that extends from the workpiece table so that the workpiece part can be discharged through the parts chute.
In some examples, a machine tool includes a hold-down device for holding the workpiece down against the support plane as the workpiece is being punched through. A stripper (e.g., a plate-shaped stripper) may be mounted to an end of the hold-down device. During the punching stroke (e.g., as the punch or a punching cutter punches through the workpiece), the stripper rests on an upper surface of the workpiece in order to hold the workpiece down against the workpiece support during the punching operation.
The hold-down device and/or the stripper can be used to discharge a workpiece part. In some examples, a punching tool includes a stepped hold-down device including an underside with first and second surfaces that do not lie in a common plane. The first surface clamps a portion severed from a remaining sheet, while the remaining sheet is unrestrained adjacent the second surface. To remove the severed sheet portion from the punching machine, the unrestrained remaining sheet can be displaced while the severed, clamped sheet portion is held securely or moved independently of the remaining sheet.
Alternatively, a workpiece part can also be discharged by moving the remaining workpiece along the support plane while the workpiece part that has been cut free is driven along the support plane and thereby pushed away from the processing region by the remaining workpiece.